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What is the difference between the independent and dependent variables.

The best way to remember the difference between independent and dependent variables is when you are conducting an experiment you are looking to see if one variable (the independent variable) has an effect on...
EH
Answered by Emily H. • Psychology tutor
9648 Views

Solve x^2 + 15x = - 50

x 2 + 15 x + 50 = 0 (rearrange by adding 50 to both sides) (x + 10)(x + 5) = 0 (factorise the quadratic equation) x + 10 = 0 or x + 5 = 0 (for the above to equal zero, at least one of the bracketed terms mus...
JS
Answered by Julia S. • Maths tutor
9889 Views

In one experiment, the temperature of 50 g of water increased from 22.0 °C to 38.4 °C. The mass of alcohol burned was 0.8 g. Calculate the heat energy (Q) in joules, released by burning 0.8 g of the alcohol.

Key Equation: Q = mc ΔT Where: Q = heat transferred (J), m = mass of substance which is heated (g), c = heat capacity of water (J g -1 °C -1 ) and ΔT = temperature change for heated substance (°C) . c = 4.2 ...
DB
Answered by David B. • Chemistry tutor
12985 Views

f(x) = 2x + c, g(x) = cx + 5, fg(x) = 6x + d. c and d are constants. Work out the value of d. 3 marks.

fg(x) = 2(cx+5) + c = 2cx+10+c [1 mark] fg(x) = 6x+d. fg(x) = 2cx+10+c 6x = 2cx and d = 10+c [2 marks] 3 = c and therefore d = 13 [3 marks]
HK
Answered by Heba K. • Maths tutor
22830 Views

balance equation : PCl5 + 4H2O → H3PO4 + HCl

fist look at the first molecule on the left of the equation, the first atom is P there's 1 mole and looking at the right there is also only one. the look at the next atom Cl which has five mole, on the right...
CM
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